Took members advice and gathered several reloading manuals(Lymans, AR15 and modern reloading 2nd edt) Even put several apps for loading data on my phone( read info while my apprentice does work). Looking to understand burn rates of powders and how implement them to reloading. Is there a book or website that anyone recommends to use. Also is there other books to add that are helpful.
Loading for AR15 right now and bolt gun in the future.
Thank you for the recommendations

https://shootersreference.com/guides/powder_burn_rates/

Collated collection of relative burn rates.  Read the notes at top - you'll never see "X grains per milisecond" type ratings.  Just how fast/slow powders burn in relation to each other.

About the only thing you can do with this is look at other potential powders to use for a given round.  You cannot extrapolate load data, etc. or any other characteristic (more gassy, cleaner burning, etc)

The Lee manual is a waste of money.  It is not original data.  It is all copied from various bullet/powder OEM sources.

For handgun the best option is Lyman 51st.  This is best resource for hard cast bullet data (which can subbed for copper plated bullets and hard cast coated bullets).
Rifle rounds are a different animal especially the solid copper ones as they are longer than a similar weight traditional lead core bullet and require a faster twist.
So there is no generic rifle manual.  But, Hornady and rest of OEM's all have good manuals.  Hornady probably is most updated manual out there.   Supplements for new not listed
bullets are usually available from the OEM web site or by calling their tech support.  

The biggest caveat to reloading rifle ammo is that rifle brass case capacity as measured in grains of water varies headstamp to headstamp.
So if you do not have the same brass then think reduce 10% and work up.

I always suggest that new reloaders buy the manual published by the company they intend to use the most bullets from.

Hornady
Sierra
Nosler
would be high on my list.

As previously posted, especially regarding .308, do not mix different headspace cases when loading warm loads. 7.62x51mm Lake City and IMI (as well as other foreign military cases) cannot use .308 data safely. Many .308 starting loads are maximums when using 7.62x51mm brass.

Simply weighing resized, trimmed and unprimed cases will give you a generic ballpark reference as to where they stand on a continuum. Heavy cases need lighter powder charges.

I never start at minimum loads, unless I actually want a minimum load. I know every manual insists on this, start low and work up. I start slightly below the halfway mark and run the rounds over my chronograph to establish a baseline. If they are faster than predicted I know I won't be able to use full power loads. If they are slower than predicted, I still respect the published maximums.

The smaller the case, the smaller increments are needed when increasing powder charges. I have no problem increasing powder charges one whole grain (1.0) in a .300 Winchester Magnum. .5 grain in .308/.30-06, .3 grain in .223. Pistols need smaller increases.

I aim for published starting load, but actually start when I get my thrower within .3 or so grains either side of it.  Then depending on results, start laddering up every .3 gr (via trickler if needed)

Manuals, get from the manufacturer you intended to use and augment with more later. I started with Sierra added Hornady l later Berger and a couple others.

Loading rifle depends on the cartridge. Some run higher than others. Gas guns and bolts are different. Shoulder bump for a semi is different than that for a bolt. Case capacities differ with each manufacturer. Brass I don't mix headstamps. Been working with Norma  on my PRC but have switched to Peterson. Getting ready to check some loading later today.

Working up loads I will usually start mid chart, but even then that can show issues. My 6mm Creedmoor AR10 was a prime example. Factory ammo pierced primers. Loaded ammo pierced primers even with the lowest charge on the table. A lot of tuning work with buffer and gas worked it out and then a final charge could be messed with.